1. Field of the Invention
The present invention relates to an ink jet recording apparatus for performing a recording operation by discharging ink. More particularly, the present invention relates to a capping mechanism for protecting a head of the ink jet recording apparatus.
2. Related Background Art
Capping means is conventionally required for the following reasons in the ink jet recording apparatus. Firstly, the capping means is required for so-called protection of a recording head such that drying of ink in a nozzle portion of the recording head is prevented and no foreign matters such as dust, etc. are attached to the nozzle during a standby operation of a recorder body. Secondly, the capping means is required as sucking means for restoring a so-called discharging state of the ink. In this restoration, the internal pressure of a cap is set to a negative pressure by separate pump means and the above foreign matters are sucked and removed in a state in which the cap comes in contact with the recording head to normally discharge the ink when the nozzle portion is clogged by the foreign matters such as dust, etc.
The capping mechanism is generally divided into two methods.
A first method utilizes the movement of a carriage mounting the recording head thereto. In a second method, the cap is operated by e.g., a paper conveying motor and a capping unit dedicated motor except for power of the carriage.
In the first method utilizing force caused by the movement of the carriage, a slide cap mechanism is used in many cases. In this slide cap mechanism, the carriage is engaged with a cap unit when the carriage reaches a capping position. The cap is moved toward the recording head by cam means simultaneously when the cap unit is slid together with the carriage. Thus, the cap is pressed against the recording head.
In the second method utilizing a motor, etc. except for power of the carriage, the operation of the cap is switched from a paper conveying state to a cap opening-closing state through a switching mechanism of this operation. Then, the carriage is moved to the capping position and the capping operation is performed. This construction is hereinafter called a motor drive capping mechanism.
However, the above motor drive capping mechanism performs an operation of the capping mechanism through the paper conveying motor or the dedicated motor. Therefore, the mechanism becomes complicated and it takes time to open and close the cap. Accordingly, a problem exists in that no throughput of print is improved when a printing operation is started from a capping state.
Further, since cost is also increased, the motor drive capping mechanism is adopted in a kind of a middle class device or more in price in many cases.
In contrast to this, the ink jet recording apparatus of the slide cap mechanism can be manufactured at low cost so that the slide cap mechanism is adopted in a device kind belonging to a spread price band in many cases.
However, in the device kind of this price band, there is also an ink jet recording apparatus with a recording head having magenta and cyan thin in density in addition to conventional four color inks (black, yellow, magenta, cyan) to print a high quality image at a photograph level in recent years. Further, there is also a recorder in which two heads can be mounted to one carriage so as to perform a high speed printing operation.
However, in the ink jet recording apparatus having two heads mounted to one carriage, a corresponding cap must come in contact with a forming face of an ink discharging port of each of the heads, or must be closely attached to this forming face.
There is an ink jet type recorder described in Japanese Patent Laid-Open Application No. 7-156419 as one example of the disclosure of such a capping mechanism. In this recorder, (1) first and second cap members seal nozzle openings of first and second ink jet recording heads directed downward and are arranged on an upper face of a slider, and this slider is rotatably arranged around a rotating shaft perpendicular to the moving direction of a carriage arranged in a central portion of the slider and is supported by a supporting member vertically moved in accordance with the movement of the carriage. (2) A The slider is rotated around the rotating shaft by moving the carriage so that a seesaw movement of the slider is made. (3) The slider is resiliently biased on a side of the ink jet recording head with respect to the recorder so that two cap members are sequentially fitted to the ink jet recording heads. Thus, capping of each of the ink jet recording heads corresponding to the plural caps is performed by a single equalizing mechanism.
However, in the construction for rotating the plural caps around one rotating shaft and arranging the plural caps in the slider making the seesaw movement, there was a case in which all the forming faces could not be necessarily precisely capped in accordance with a mounting state of the ink jet recording head to the carriage and a dispersion in manufacture of each of constructional members of the ink jet recording head, etc. Further, as the number of ink jet recording heads is increased, the equalizing mechanism of the cap slider becomes complicated. Furthermore, a problem also exists in that capping accuracy is reduced and manufacturing cost is increased.
An object of the present invention is to provide an ink jet recording apparatus having a simple construction and able to position a cap covering an ink discharging port of an ink jet recording head or protecting the ink jet recording head with high accuracy with respect to the ink jet recording head.
Another object of the present invention is to provide an ink jet recording apparatus having a simple construction and a capping mechanism with respect to the ink jet recording head able to reliably cover the ink discharging port of the ink jet recording head or reliably protect the ink jet recording head.
Another object of the present invention is to provide an ink jet recording apparatus which mounts an ink jet recording head for discharging ink from an ink discharging port and has a carriage moved to a recording position opposed to a recording medium and a capping position opposed to a cap for covering the ink discharging port, the ink jet recording apparatus comprising: a cap holder for holding the cap for covering the ink discharging port; a cap slider which holds the cap holder and a resilient member for resiliently biasing the cap to a side of the ink jet recording head in the capping position, and is moved in the same direction as a moving direction of the carriage together with the movement of the carriage in accordance with the movement of the carriage to the capping position; and a slider holding mechanism which movably supports the cap slider in the moving direction and has a mechanism for displacing the cap holder to the ink jet recording head side in the capping position in accordance with the movement of the cap slider.
Another object of the present invention is to provide an ink jet recording apparatus able to simultaneously mount plural recording heads to a carriage and performing a recording operation by discharging ink, the apparatus comprising: a plurality of caps for protecting nozzles of the respective recording heads; a cap holder for holding the plural caps; a cap slider for holding the cap holder and slid by contact with the carriage; and a cam face for moving the cap slider toward each of the recording heads in a capping position, wherein the cap holder and the cap slider are fitted to each other in a scanning direction of the carriage; and the cap slider has a first positioning member hitting against the carriage in the scanning direction of the carriage; and the first positioning member is fitted to the cap holder and positions the cap holder and the cap slider in the scanning direction of the carriage, the cap-slider further has a second positioning member; and the second positioning member positions the cap holder and the cap slider in a direction different from the scanning direction of the carriage; and the second positioning member is fitted to the carriage in the capping position and positions the carriage and the caps, and the caps are further arranged in the vicinity of the first and second positioning members on the cap holder; and the cap holder is pressurized by a spring approximately from just below the caps to press the caps against the recording heads in the capping position.
Another object of the present invention is to provide an ink jet recording apparatus constructed such that recording heads on a carriage can be exchanged in accordance with a using object, the ink jet recording apparatus comprising: a plurality of caps for protecting nozzles of the respective recording heads; a cap holder for holding the plural caps; a cap slider for holding the cap holder and slid by contact with the carriage; and a cam face for moving the cap slider toward each of the recording heads in a capping position, wherein the cap holder and the cap slider are fitted to each other in a scanning direction of the carriage; and the cap slider has a first positioning member hitting against the carriage in the scanning direction of the carriage and also has a third positioning member hitting against the carriage in a vertical direction with respect to a sheet face of recording paper; and the first positioning member is fitted to the cap holder and positions the cap holder and the cap slider in the scanning direction of the carriage, the cap slider further has a second positioning member; and the second positioning member positions the cap holder and the cap slider in a direction different from the scanning direction of the carriage; and the second positioning member is fitted to the carriage in the capping position and positions the carriage and the caps, and the cap holder is further pressurized by springs approximately from just below the third positioning member and approximately from just below the caps according to the recording heads to press the caps against the recording heads in the capping position.